Sensors For Estimating Properties Of A Core

Abstract

A method for estimating a property downhole is provided, which, in one aspect, may include receiving a core at a receiving end of a downhole tool while removing a portion of the received core distal from the receiving end of the tool, obtaining measurements by a sensor downhole, and processing the measurements to estimate the property of interest.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application takes priority from U.S. Provisional Patent Application Ser. No. 60 / 975,065, filed on Sep. 25, 2007.BACKGROUND OF THE DISCLOSURE[0002]1. Field of the Disclosure[0003]The disclosure herein relates generally to obtaining cores from a formation and estimating one or more properties of interest downhole.[0004]2. Description of the Related Art[0005]To obtain hydrocarbons such as oil and gas, wells (also referred to as “wellbores” or “boreholes”) are drilled by rotating a drill bit attached at a bottom end of a drill string. The drill string typically includes a tubular member (made by joining pipe sections) attached to a top end of a drilling assembly (also referred to as the “bottomhole assembly” or “BHA”) that has a coring drill bit (or “coring bit”) at the bottom end of a drilling assembly. The coring bit has a through-hole or mouth of a selected diameter sufficient to enable the core to enter into a cylindrical coring barr...

AI Technical Summary

Benefits of technology

The present patent provides systems, apparatus, and methods for continuous or substantially continuous coring of a subsurface formation. This involves drilling into a formation to retrieve a core, receiving the core into a chamber, and removing a portion of the core uphole of the open end of the chamber so as to continue to receive the core as the drilling continues. The systems and methods allow for continuous coring operations and selectively storing core samples obtained at different formation depths. Additionally, the patent provides methods for estimating a property of a core and performing tomography of a continuously obtained core using at least one sensor placed proximate to the core.

Problems solved by technology

Such systems, therefore, are not conducive to continuous coring (coring beyond the core barrel length) or for taking measurements of cores longer than the core barrel length.

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